Restricting usage of IP addresses as hyperlink references

You and your customer’s security is paramount in our day-to-day operations. In our continued efforts to this commitment, we would like to inform you of an upcoming change in the type of links that our system will allow you to redirect users to and track. Beginning March 7, 2016, we will no longer allow direct IP addresses to be used in rewritten links (tracked links) sent via Sailthru’s campaign or transactional messages. This only affects your message if you use a direct IP address as a hyperlink reference, i.e. “”. While IP addresses often correlate to an exact location of hardware, they do not offer the end user transparency about where they are being directed. IP addresses in hyperlinks are often the mark of phishing attacks or other malicious attempts to gain personal information. The ability for your users to always see your domain name in their address bar is critical to building brand trust, especially for commerce businesses. After March 7, 2016, if an IP address is used as a hyperlink reference, the link will redirect to a generic error page and return the HTTP response code 400. This change allows us to adhere to deliverability best practices, protecting your users, your brand, and ultimately your business. If you have any questions about this change, please contact your Customer Success team member or support@sailthru.com.